Question 948221
1. Mr. Alvarado is 20 years old older than his son. In 5 years, he will be 5 years more than twice as old as his son will then be. Find their present ages.
f = s + 20
f+5 = 2s+5
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Substitute for "f"::
s+20+5 = 2s+5
s = 20 years (son's age now)
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 2. The sum of the ages of Sam and Tomas is 27 years. Seven years ago, Tomas was three years more than one-fourth as old as Sam. Find their present ages.
s + t = 27
t-7 = (1/4)s + 3
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Substitute for "t" and solve for "s"::
27-s - 7 = (1/4)s + 3
20-s = (1/4)s + 3
(5/4)s = 17
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s = 68/5
s = 13 3/5 years (Sam's age now)
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Solve for "t"::
t = 20-s
t = 6 2/5 years (Tomas's age now)
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 3. Rosa is twice as old as pilar. In four years, Rosa's age will be 2 years less than pilar's age 3 years ago. Find their present ages.
r = 2p
r+4 = p-3-2
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Substitute for "r" and solve for "p"::
2p+4 = p - 5
p = -9
Note: Pilar's age cannot be negative.
Please check your problem statement.
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Cheers,
Stan H.
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